Since the sizes of discharge sources that generate partial discharges in power devices are mostly very small, it is difficult to accurately measure the location of a partial discharge and find and eliminate a discharge source. Accordingly, technology for measuring the location of a partial discharge is technology that is very important in the prevention of a failure in a power device.
Technology for measuring the location of a partial discharge may be divided into a method using attenuation attributable to the propagation of an electromagnetic wave discharge signal generated by a discharge, and a method using the differences between the times at which an electromagnetic wave discharge signal arrives at partial discharge sensors.
The former method using propagation attenuation is problematic in that it is difficult to maintain the intervals between the partial discharge sensors and signals detected by the partial discharge sensor are attenuated or deformed while being transferred to a measuring device, thereby reducing the reliability of the location information of a discharge. The latter method using the differences between the times at which an electromagnetic wave discharge signal arrives at partial discharge sensors is problematic in that a partial discharge signal is not transferred to the partial discharge sensors along rectilinear paths due to the internal structure of a power device, and thus an error occurs between the theoretical time of arrival and the actual time of arrival, thereby reducing the accuracy of estimation of a location.
In particular, a method of calculating the location of a partial discharge by applying the differences in the time of arrival of a partial discharge signal to a simultaneous equation numerical analysis algorithm was proposed. However, when the initial value of the simultaneous equation numerical analysis algorithm is erroneously set, the conventional method is problematic in that convergence speed is slow and diverging from the actual location of a partial discharge, rather than converging to the location, is performed.